The invention relates to a semiconductor module having semiconductor chips disposed in different planes in a housing. U.S. Pat. No. 5,128,831 describes a configuration in which a conductive connection is established between chip carriers after individual semiconductor chips with their chip carriers have been provided one above the other. In order to produce the conductive connection, the entire module is dipped into a solder bath and a local vacuum is applied to the openings in order to suck the solder into the openings and thus establish conductive soldered connections between the individual planes of the semiconductor chips or of the chip carriers. This method is relatively complicated since, on the one hand, a vacuum environment has to be provided and, on the other hand, appropriate tightness of the semiconductor module also has to be ensured. On the other hand, there is the risk of contamination or short circuits in the semiconductor module if the liquid solder composition escapes from the openings.
It is accordingly an object of the invention to provide a semiconductor module which overcomes the above-mentioned disadvantages of the heretofore-known semiconductor modules of this general type and which can be produced in a simple and reliable manner.
With the foregoing and other objects in view there is provided, in accordance with a first embodiment of the invention, a semiconductor module, including:
a housing;
a first chip carrier formed with a first opening and a second chip carrier formed with a second opening, the first and second chip carriers disposed in the housing and stacked on top of each other;
a first semiconductor chip provided on the first chip carrier and a second semiconductor chip provided on the second chip carrier; and
a conductive plug-in connection electrically connected to the first and second semiconductor chips, the conductive plug-in connection extending through the first and second openings.
In other words, a semiconductor module is provided in which semiconductor chips are disposed in a housing, in particular in a common housing. The semiconductor chips are provided on chip carriers. Each semiconductor chip may be provided on a separate chip carrier. Alternatively a plurality of semiconductor chips may be provided on a common chip carrier. At least some of the semiconductor chips with their respective chip carrier are in this case provided one above the other, thereby producing a stacked configuration of the semiconductor chips. A conductive connection is provided between the chip carriers disposed one above the other and, if appropriate, also next to one another. The conductive connections lead through openings in the chip carriers and a conductive connection is in each case established from the openings to the semiconductor chips, or to at least one of the contacts of the semiconductor chip.
In the case of the first embodiment of the invention, the semiconductor module has a plurality of semiconductor chips, which are disposed in a housing in a manner such that they are each provided on a chip carrier. At least some of the semiconductor chips with their chip carriers are provided one above the other and there are conductive connections between the chip carriers of the semiconductor chips disposed one above the other. The conductive connections between the chip carriers are formed by plug-in connections, they lead through openings in the chip carriers and are conductively connected to the semiconductor chips. Such plug-in connections are simple to produce and also easy to handle. The use of a liquid solder composition or the necessity of sealing the component is thus obviated.
The plug-in connections may either be provided in a releasable manner in the semiconductor module, with the result that, for repair purposes for example, defective semiconductor chips are removed from the module. However, the plug-in connections may also be connected to at least one of the chip carriers by a soldered connection.
With the objects of the invention in view there is also provided, in accordance with a second embodiment of the invention, a semiconductor module, including:
a housing;
a first chip carrier formed with a first opening and a second chip carrier formed with a second opening, the first and second chip carriers disposed in the housing and disposed one above the other, the first and second openings each being lined with a conductive layer;
a first semiconductor chip provided on the first chip carrier and a second semiconductor chip provided on the second chip carrier; and
an intermediate layer provided between the first chip carrier and the second chip carrier; and
a first conductive projection and a second conductive projection electrically connected to one another and disposed opposite from one another on the intermediate layer, the first conductive projection at least partly engaging into the first opening, the second conductive projection at least partly engaging into the second opening.
In other words, the second embodiment of the invention provides a semiconductor module having a plurality of semiconductor chips, which are disposed in a housing. At least some of the semiconductor chips disposed on respective chip carriers are provided one above the other and there are conductive connections between the chip carriers of the semiconductor chips provided one above the other. The connections lead through openings in the chip carriers. The openings are lined with a conductive layer. Intermediate layers are provided between the semiconductor chips disposed one above the other or between the chip carrier of one semiconductor chip and the semiconductor chip provided underneath. The intermediate layers have conductive projections, which at least partly engage in the openings of neighboring chip carriers, thereby ensuring mechanical retention between the intermediate layer and the respectively neighboring carrier. Mutually opposite projections are conductively connected to one another.
The projections may be shaped such that they can be fitted in a positively locking manner into an adjoining opening. In this case, the diameter of the projection corresponds to the diameter of the opening. However, it may also be provided that the dimensions of the projections are chosen to be greater than the dimensions of the openings. In that case, however, the projections must be formed similarly to a truncated cone, such that at least some of the projections protrude into the opening in the form of a tip, in which case, on a circumferential line of its cone shape, the projection bears on the edge of the opening and thus establishes the conductive contact with the conductive layer in the opening. In order to ensure a continuous conductive connection between a plurality of planes of the semiconductor module, mutually opposite projections of the intermediate layer are conductively connected to one another.
The intermediate layers may be provided in a releasable manner in the semiconductor module, with the result that individual semiconductor chips or individual chip carriers with the semiconductor chips provided thereon can be removed from the module, for example in order to replace defective semiconductor chips. However, the intermediate layers may also be connected to at least one of the chip carriers by a soldered connection.
The conductive connections in the semiconductor module can, in principle, extend over all the planes of the semiconductor module, that is to say over all the planes of the semiconductor chips and chip carriers provided one above the other. However, the conductive connections may be configured such that they respectively extend only over some of the planes of the chip carriers disposed one above the other, in order thus to connect to one another only some of the semiconductor chips provided one above the other.
In accordance with another feature of the invention, a thermally conducting layer is provided between the first and second semiconductor chips.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a semiconductor module having interconnected semiconductor chips provided one above the other, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.